JPS6260976B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for connecting vulcanized rubber waterproof sheets. More specifically, the present invention relates to a method of connecting vulcanized rubber waterproof sheets by wrapping them together. [Prior Art] Conventionally, there are two methods for connecting ends of vulcanized rubber waterproof sheets by wrapping them together: an adhesive application method and an unvulcanized rubber sheet connection method. The adhesive application method involves applying rubber glue or emulsion adhesive to the ends of adjacent waterproof sheets to be connected, drying at room temperature, then wrapping those ends together, and then pressing the lapped parts. It is done by doing. However, this adhesive application method requires a curing period of about one day to two weeks for the rubber glue or emulsion adhesive to completely adhere. This is because the solvent in the rubber glue or the moisture in the emulsion adhesive remains between the laps, weakening the adhesion between the rubber in the rubber glue and the resin in the emulsion adhesive, and causing blistering defects due to volatilization of the solvent. In this case, if the adhesive is dried at a high temperature to completely volatilize the solvent or water content of the applied rubber glue or emulsion adhesive, adhesiveness will be lost. Moreover, during this curing period of about 1 day to 2 weeks, troubles such as the lap joints peeling off due to external factors such as shrinkage of the sheet and walking of the worker occur, which may result in a water leakage accident. On the other hand, in the method of connecting unvulcanized rubber sheets, an adhesive unvulcanized rubber tape is sandwiched between the laps of the ends of adjacent vulcanized rubber waterproof sheets to be connected, and the tape is pressed and heated from the outside with a press machine to connect them. However, this press machine is large and difficult to transport to the site, and the work efficiency is low as it connects each sheet one by one.Furthermore, it is difficult to connect the ends of the vulcanized rubber tarpaulin sheet, which is the base surface of the tarpaulin sheet construction. The problem is that the adhesive strength is poor because it cannot be heated. [Problems to be Solved by the Invention] The present invention has been made based on the above points, and its purpose is to eliminate the drawbacks of the above-mentioned prior art, to enable quick connection, and to provide quick connection after connection. The object of the present invention is to provide a method for connecting vulcanized rubber waterproof sheets that can provide a connection portion with high adhesive strength. [Means for Solving the Problems] The gist of the method for connecting vulcanized rubber waterproof sheets of the present invention is to form a coating layer of a thermoplastic rubber solution on the edge of a vulcanized rubber waterproof sheet, The process involves heating and melting the layers with hot air and then pressurizing and fusing them. In the present invention, the thermoplastic rubber may be any material that can be dissolved in a solvent and coated, such as a styrene-butadiene block polymer, a styrene-isobutylene block polymer, an ethylene-vinyl acetate polymer, and the like. Alternatively, a blend of these with synthetic resins, general-purpose rubbers, tackifiers, plasticizers, fillers, etc. may be used. [Function] The method for connecting a vulcanized rubber waterproof sheet of the present invention involves forming a coating layer of a thermoplastic rubber solution on the end of a vulcanized rubber waterproof sheet, and heating the coating layer with hot air to connect the thermoplastic rubber solution. The purpose is to completely volatilize and burn off the solvent in the coating layer of the solution, as well as melt it, and firmly pressurize and fuse the lub in the molten state. [Example] Next, an example of the method for connecting a vulcanized rubber waterproof sheet of the present invention will be described with reference to FIGS. 1 and 2. First, prepare the vulcanized rubber waterproof sheet 1 to be connected and a 30% solution of Kraton G1650 (trade name of thermoplastic rubber manufactured by Ciel Chemical Co., Ltd.) in toluene. Next, a 30% solution of Kraton G1650 is applied to a 50 mm wide portion of the end portion of the vulcanized rubber waterproof sheet 1 that will be the lap portion, and then dried at room temperature for 30 minutes to form a coating layer 2. FIG. 1 shows the obtained sulfur rubber waterproof sheet 1 with a coating layer 2 added thereto. Next, the sulfur rubber waterproof sheet 1 with coating layers 2 added thereto shown in FIG. 1 is wrapped so that the coating layers 2 face each other. Then, lift the coated layer 2 slightly so that hot air can blow through the boundary surface where they are wrapped so that they are facing each other, and apply a general-purpose hot air gun to the boundary surface.
Hot air is sent by a hot air blower 3 such as a flame blower to heat and melt the coating layer 2 and completely volatilize the remaining solvent. Immediately thereafter, the molten coating layer 2 is completely wrapped, and the wrapped portion is pressurized and fused using a roll 4. In the method for connecting a vulcanized rubber waterproof sheet of the present invention,
The solvent in coating layer 2 is almost volatilized by drying at room temperature.
Furthermore, it is completely volatilized by heating with hot air. Therefore, there is no possibility that the lap joint will bulge due to residual solvent. Moreover, the thermoplastic rubber coating layer 2 maintains its thermal meltability even when heated with hot air. Next, the shear adhesive strength of the joints of the thus obtained vulcanized rubber waterproof sheet of the present invention and the joints of a vulcanized rubber waterproof sheet connected by a conventional connection method as comparative data were measured. Comparison materials include conventional chloroprene adhesive,
A butyl rubber adhesive is bonded between the laps. Table 1 shows the measurement results.

[Table] As can be seen from Table 1, the connections obtained by the vulcanized rubber tarpaulin sheet connection method of the present invention have strong adhesion, do not require any curing period, and have no blistering defects. It is something. [Effects of the Invention] According to the method for connecting vulcanized rubber tarpaulin sheets of the present invention, there is no need for a curing period after the connection work is completed, and strong fusion bonding occurs immediately, and the connection is highly reliable without any blistering defects. It is industrially useful.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a coating layer-added sulfur rubber waterproof sheet used in an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing an embodiment of the present invention. 1: Vulcanized rubber waterproof sheet, 2: Coating layer, 3: Hot air machine, 4: Roll.

Claims (1)

[Claims] 1. In a method for connecting vulcanized rubber waterproof sheets by wrapping and connecting the ends of adjacent vulcanized rubber waterproof sheets, a thermoplastic rubber organic solvent solution is applied to at least one end of the vulcanized rubber waterproof sheets. A method for connecting vulcanized rubber waterproof sheets, which comprises drying to form a coating layer, blowing hot air onto the coating layer to melt it, and then pressurizing and fusing the coating layer through the molten coating layer.